class_docstr: Sigmoid cross entropy gradient function.
class_docstr_tok: ["Sigmoid","cross","entropy","gradient","function","."]
code: def __init__(self, reduce, count, ignore_mask, t):
      self.reduce = reduce
      self.count = count
      self.ignore_mask = ignore_mask
      self.t = t
  
file_path: chainer/chainer/functions/loss/sigmoid_cross_entropy.py
imports: import chainer
  from chainer import backend
  from chainer import function_node
  from chainer.functions.activation import sigmoid
  from chainer import utils
  from chainer.utils import type_check
label_desc: Use image node_id 1 to create a new SigmoidCrossEntropyGrad object from inherited base classes: function_node with example: obj = SigmoidCrossEntropyGrad(reduce, count, ignore_mask, t)